OnEditEnabler.java 文件源码

public void listenTo(TextBoxBase tb) {
  strings.put(tb, tb.getText().trim());
  tb.addKeyPressHandler(this);

  // Is there another way to capture middle button X11 pastes in browsers
  // which do not yet support ONPASTE events (Firefox)?
  tb.addMouseUpHandler(this);

  // Resetting the "original text" on focus ensures that we are
  // up to date with non-user updates of the text (calls to
  // setText()...) and also up to date with user changes which
  // occurred after enabling "widget".
  tb.addFocusHandler(
      new FocusHandler() {
        @Override
        public void onFocus(FocusEvent event) {
          strings.put(tb, tb.getText().trim());
        }
      });

  // CTRL-V Pastes in Chrome seem only detectable via BrowserEvents or
  // KeyDownEvents, the latter is better.
  tb.addKeyDownHandler(this);
}